Alfhed tingle



Aug. 21, 1923. 1,465,882 I v A. TINGLE PULP ARTICLE Filed Sept. 24 1921 I 6 gzifzg J Q B Llama-[nun ass PxmcI/Hmvr/ssa Sunrac:

Patented Aug. 21, 1923.

time Tame er 1 s;

ALFRED TINGLE, oFoT'rAwA, on'rmmo, camera.

PULP Annota- T 0 all whom it may concern:

- Be it known that I, ALFRED TINGLE, a

subject of the King of Great Britain, and resident of the city of Ottawa, in the Province of'Ontario and Dominion of Canada, have invented certain new and useful Tm? provements in Pulp Articles, of which the following is a specification.

This invention relates to improvements in pulp articles, and the objects of the invention are to provide an article having a relatively'impermeable surface and designed to receive a coat of varnish or other material which may be manufactured at low cost from ligno-cellulose pulp.

' It is well known in the art to manufacture pressed pulp articles impregnated with a solution of a gum, or resinor a varnish to stiffen the same, In this instance, relatively large quantities of gum, resin or varnish are I to the surface after removal of the acid and drying as hereinafter described.

The drawing shows a diagrammatic sec: tional view of an embodiment of the invention.

The process maybe applied to a variety of articles for a variety of purposes. It comprises in its main essentials, first, treating the article superficially with sulphuric acid of a suitable density, then neutralizing the sulphuric acid and washing the surface, then drying the article and applying the first coating which may be varnish or the like. The'length of time occupied in the superficial treatment of the sulphuric acid will depend somewhat on'the strength of the acid. I have found that acid maybe used of a strength comparable with that heretofore" used in the art of manufacturing vegetable parchment by the treatment of a purely cellulose paper with sulphuric acid. The densityused for this purpose ranges from 52 to B. With the strong acid, the length of superficial treatment may be reduced. '1

j in my co-pending Application filed- September 24, 1921. Serial No, 503,048.

find it more convenient to give. this treatment by immersing the article in a tank containing the acid, and, for the purpose of illustration, will now describe the process in detail as applied, for instance, to the manufacture of a pressed. pulp pail to be usedfor food products. i

In practically carrying out this process,

the pails are suitably formed from pulp fibre of a desired size and shape in a manner well known in the art. These are allowedto become relatively dry and then immersed in a tankcontaining sulphuric 'acid (say, 55 B.) the immersion preferably being for not less than one minute and not more than three minutes. The pail is then'raised and allowed to drip for, ,say, one-half minute, and washedwith running water fortwo minutes or more. The pail is then washed with weak ammonia (10% ammonia 26 B. and 90% water by volume), washing being carried on for a periodof two minutes or more. The pail is then inserted in a stronger soluand 80% water by volume) for five minutes or more, which .p'ail may- ,then be again washed in running-water for three minutes or more. 7 v

The purpose of the ammonia and various washings is to remove the last trace of .sul-

the article. After this has been. accomplished, the artiele is dried in a kilnat about 180 Fahrenheit. V v The process thusfa'r described isclaimed application, Serial No.

It willbe found inthis condition the sulphuric acid has produced a relativelyv impermeable compound, the chmicalconstitution of which ll, am unable to state, but which rendersthe surface a light brown and relatively impermeable by varnish or other cov- 'tion of ammonia (20% ammonia 26f B. l

phuric acid and'its salts from the surface of ering and of a parchmentized character.

The articlefor some purposes might be used without av covering, but, whenit is to be used as a. pail for packing food products, it i is dipped after dryihg in avarnish which is relatlyely impermeable by water and notacted upon by the food product to be packed.-

The varnish'is then dried by heating the article in the art/ v I The drawing shows a portion of a sheet. of pulp fibre or ligno-cellulose ha a manner well understoodin the body portion A of li no-cellulose with a:

/ parchmentized surface on each side of the body portion, the said surface B being in turn coated with a coating of varnish C as previously set forth and described.

It will appear. from observation that the effect of the sulphuric acid is to produce a hydrated form of cellulose or ligno-cellulose on the surface of the article. I am aware that it has long been proposed to manufacture vegetable parchment by above process and many apparently widely difierent embodiments of my invention within the scope of the claims, constructed with out departing from the spirit or scope thereof, itis intended that all matter contained in the accompanying specification shall be I neeegeea interpreted as illustrative and nht in a limiting sense. 7

What ll claim as my invention 1s:

1. As a' new article of manufacture, superficially parchmentized ligno-cellulose having an untreated body portion. i

2. As a new article of. manufacture, pressed and superficially parchmentized pulp having an untreated body portion.'

3. Asanew article of manufacture, superficially parchmentiz ed ligno-cellulose' having a varnished-surface.

4. As a new article of manufacture, a pressed pulp article formed from lig'no-cel lulo se having the surface hydrated and relatively impermeable by varnish and the like.

5. As a new article of manufacture, a pressed pulp article formed from ligno-cellulos'e having the surface hydra-ted and elatively impermeable by varnish and the ike, and a coating of varnish on the surface.

In witness whereof I" have hereunto set my hand in the presence of a witness.

ALFRED 'rnaern Witness a v Russian S. SMART. 

